The video was recorded by a reporter for The Arizona Republic at 8:36 p.m. from an area near the intersection of Second and Monroe streets in downtown Phoenix. That's the spot where thousands gathered to protest the president and his supporters.

Seconds prior to the object hitting the officer, yellow smoke rises from something on the side of the street where the protesters are standing. While the scene already is tense, it escalates seconds after the projectile hits the officer, who is standing in line with other law-enforcement members.

Protesters leave the scene after Phoenix police used gas outside the Phoenix Convention Center on Aug. 22, 2017, in Phoenix. Protests were held against President Donald Trump as he hosted a rally inside the convention center. Associated Press

Protesters raise their hands after Phoenix police used gas outside the Phoenix Convention Center on Aug. 22, 2017, in Phoenix. Protests were held against President Donald Trump as he hosted a rally inside the convention center. Associated Press

Smoke billows after Phoenix police used gas outside the Phoenix Convention Center on Aug. 22, 2017, in Phoenix. Protests were held against President Donald Trump as he hosted a rally inside the convention center. Associated Press

Protesters yell after Phoenix police used gas outside the Phoenix Convention Center on Aug. 22, 2017, in Phoenix. Protests were held against President Donald Trump as he hosted a rally inside the convention center. Associated Press

Phoenix police move protesters away after using tear gas outside the Phoenix Convention Center on Aug. 22, 2017, in Phoenix. Protests were held against President Donald Trump as he hosted a rally inside the convention center. Associated Press

Phoenix police move protesters away after using gas outside the Phoenix Convention Center on Aug. 22, 2017, in Phoenix. Protests were held against President Donald Trump as he hosted a rally inside the convention center. Associated Press